4.5 understand how abiotic and biotic factors affect the population size and distribution of organisms

Abiotic Factors:
- Non-living environmental factors can affect organisms in an ecosystem.
Examples include: light intensity, soil pH, temperature, soil moisture, minerals and nutrients in the soil, oxygen levels, carbon dioxide levels, availability of water.

Biotic Factors:
- Living interactions between organisms, that will affect ALL species (as they have the vulnerability of being food to predators or host to disease).
Examples include: diseases, predation, competition for food, competition for shelter, bacteria, fungi.